With the extension of the application area of display device, the display device is no longer limited in the demand for flat panel display. The demand for a multi-facet display device design has already existed nowadays. Such multi-facet display device generally comprises multiple flat display panels assembled together with each panel displaying in a respective direction. The multi-facet display device may be, for example, a light box. The images displayed on respective display panels of such multi-facet display device are independent with respective to each other. There are sharp edges and corners located at the joint of adjacent display panels, which makes it impossible to achieve image continuity among respective directions.